If nobody have this for the F20 - anyone with other experience with QUAIFE LSD and other BMW's?

I know a few BMW owners who have installed Quaife LSD in their BMWs. They have been positive about it. One of them installed it in an E92 335i, and he was probably the first guy to do so, as Quaife did not know at the time that the internals of the differential were welded together. This caused some complications that were sorted out eventually.

The Quaife unit is not as suited for drifting as clutch pack differentials, but very efficient for going early on the throttle out of corners. It also works well together with the traction control. The LSD sometimes needs a little bit of help from the traction control to start working in very slippery conditions.

Probably none--not while it's still under lease anyway. But I know from personal experience how much an LSD contributes to the purity of the driving experience. And few people would deny that the elimination of an LSD on the spec sheet was done at the behest of BMW's marketing department.

But I would want to be convinced that the diff could be swapped over without doing any damage and otherwise not losing any functionality in the electronic control system.

Been there done that in the old 135i. No impact on the electronics at all. Makes a HUGE difference to how the car drives. Much more predictable tail end and you can drift at will.

But the old 135i did not have electronic differential brake when the stability control was switched off, did it? This system enables you to drift the car, although not quite as easily as with a real limited slip differential.

When buying our 116i, I was convinced that I would upgrade it with a Quaife unit. My previous 3 BMWs all got LSDs built in. After testing the F20 on dry tracks, wet tracks and snow/ice-tracks, I have pretty much come to the conclusion that I don't need the LSD. The stock system works surprisingly well.

But the old 135i did not have electronic differential brake when the stability control was switched off, did it? This system enables you to drift the car, although not quite as easily as with a real limited slip differential.

When buying our 116i, I was convinced that I would upgrade it with a Quaife unit. My previous 3 BMWs all got LSDs built in. After testing the F20 on dry tracks, wet tracks and snow/ice-tracks, I have pretty much come to the conclusion that I don't need the LSD. The stock system works surprisingly well.

I am sure the M135i deserves a Quaife, though.

Yes the old one does have e-diff as well. I'm sure it has been improved but I just can't see how it can be as good as the real thing.

But I believe the e-diff was disabled on the old generetion 1-series when you disabled the stability control?

I don't know for sure, but I would have thought its the other way around? Ie. it comes on when you turn DSC off? It makes much more sense. But I can tell you from a driver's perspective, I was able to slide my Drexler equipped 135i with ease, where it wasn't so simple previously. I suspect it would be the same with my new car M135i.

I don't know for sure, but I would have thought its the other way around? Ie. it comes on when you turn DSC off? It makes much more sense. But I can tell you from a driver's perspective, I was able to slide my Drexler equipped 135i with ease, where it wasn't so simple previously. I suspect it would be the same with my new car M135i.

When BMW launched the F20, they wrote in the ads that the e-diff now works with DSC off. I am pretty sure the earlier models worked differently.

Thinking about how it logically should work does not make much sense here. If it did, the modern BMWs would not select comfort mode when you disable DSC.

Our 116i can drift quite easily with DSC off in slippery conditions. Lack of power makes it difficult on dry tarmac. If the diff was open with no e-diff, it would have been more unpredictable.

You can feel the e-diff working on corner exits on dry tarmac as well in the 116i. When I don't have enough power to spin the outer rear tire at full throttle after apex, you would expect the car to understeer. After all, it has a weight shift to the rear tires. The e-diff brakes the inside rear tire, creating torque vectoring that tries to turn the car into the corner. This kills the understeer, and allows me to go very early on the throttle.

No, I agree with Way. It makes no sense to disable the e-diff with DSC off. I think the selection of comfort mode is to reduce throttle response, and reduce the propensity of the car to be destabilized by driver who doesn't know what he is doing.. Car makers want their cars to fail safe.

No, I agree with Way. It makes no sense to disable the e-diff with DSC off. I think the selection of comfort mode is to reduce throttle response, and reduce the propensity of the car to be destabilized by driver who doesn't know what he is doing.. Car makers want their cars to fail safe.

But even though it made no sense to disable the e-diff with DSC off, that was how it was done on earlier models. I have never driven a BMW before the F20 that had e-diff enabled with DSC off. Some purists will say that when you disable the driving aids, they should all be completely off.

And why would drivers who don't know what they are doing want to disable the DSC?

I've just looked it up. The old 135i's e-diff only works with DSC turned off completely. I could swing the tail out on the 135i before I put the Drexler on, but it wasn't as consistent and you cook the rear brakes. And on the track, there is no comparison. Mechanical diff was far superior in feel.

seems very stable and controllable to me , impressed. power is getting to both wheels and is getting managed. Id sat thats pretty impressive for traction control

That driving is done in DSC off mode, which disables the traction control, otherwise wheelspin would not be allowed. The electronic differential brake works surprisingly well. I have tried to drift our 116i on a gokart track, and it only failed due to low power and sloppy throttle response. I think I could have told the difference if the car was equipped with a real, mechanical differential brake in a blind test, but the difference is rather small from the driver's seat.

Most drivers without track driving and drifting experience would probably not be able to tell that the LSD is missing.